Internal grinder for steel ingot mould

ABSTRACT

An elongated arm having a grinding wheel turnably mounted at its front end is supported by a cylindrical bearing to rotate about an axis of the arm. The bearing is pivotally received upon a work head which is reciprocal for a predetermined length on a carriage. At the lower fore portion of the bearing, there is provided adjusting means to adjust the angle of elevation of the arm. The adjusting means runs along the upper surface of a copying surface plate, the surface plate also being adjustable in its angle of elevation.

United States Patent 7/1923 Mikaelson et a1 2,750,714 6/1956 Mueh1ing 51/35 X 3,245,176 4/1966 Muehling 51/47 X 3,335,525 8/1967 Muehling 51/47 X Primary Examiner-Lester M. Swingle Attorney-Eliot S. Gerber ABSTRACT: An elongated arm having a grinding wheel turnably mounted at its front end is supported by a cylindrical bearing to rotate about an axis of the arm. The bearing is pivotally received upon a work head which is reciprocal for a predetermined length on a carriage. At the lower fore portion of the bearing, there is provided adjusting means to adjust the angle of elevation of the arm. The adjusting means runs along the upper surface of a copying surface plate, the surface plate also being adjustable in its angle of elevation.

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aa ti INVENTOR YOSHM'AMF MA v BY 6:51 N" ATTORNEY INTERNAL GRINDER FOR STEEL'INGOT Motrin DISCLOSURE This invention relates to an internal grinder for a steel ingot mould.

Melted iron produced in an open-hearth furnace, a Bessemer converter or an electricfurnace is poured into a mould to form a steel ingot. A large mould of this kind weighs sometimes more than 25 tons. Therefore, it is desirable to grind the inner surface of the mould without moving the mould. The grinding of the inner surface of the mould is required because the inner surface thereof is melted and deformed when it is used many-times and it may become cracked in any direction, with the harmful result that slug becomes attached in the cracks. As the mould is exposed to the high temperature of melted iron many times, its inner surface becomes so hard as to make its grinding difficult.

In a conventional grinding operation, the inside of the mould has been ground by moving a wagon-shaped handoperated grinder, a portable grinder, or the like, in the right and left directions while moving it back and forth. The mould surface, after being ground, may still retain lateral injuries which give the same lateral injuries to steel ingots in the mould. Such lateral injuries remain as fatal injuries to the products produced by the rolling mills from such ingots. In addition, the conventional grinders have had many defects in that their operational efficiency is extremely bad, that small moulds and special moulds are not ground effectively, and that smooth surfaces can rarely be obtained.

An objective of the present invention is to provide an internal grinder for a steel ingot mould free from the conventional defects as mentioned above, wherein lateral injuries are not formed by grinding, the grinding can correspond to any shape of the inner surfaces of the mould to be ground and to any uneven inner surface thereof, caused by dissimilarity of degrees of melting and the difficulty of an alignment operation caused the the heavy weight of the mould, is eliminated.

According to the present invention, a grinding wheel is turnable mounted at one side of the tip of an elongated arm. The arm is supported, by a cylindrical bearing, to rotate about an axis of the arm together with drive means for the grinding wheel. The bearing is received upon a work head which moves partially in the vertical direction along a plane passing through the axis of the arm. The work head comprises means to reciprocate the work head automatically on a carriage for a predetermined length along the lengthwise direction of the carriage. At the lower foreportion of the bearing, there is provided an adjusting means to determine the angle of elevation of the arm. The adjusting means has a wheel at the lower end thereof to run upon a copying surface plate which is pivoted at the fore end thereof to a carriage and movable partially about a pivot along a vertical plane including the axis of the arm. Therefore, the work head is reciprocated above the carriage and the arm having the grinding wheel at the tip thereof is reciprocated along the copying surface plate. The carriage is moved above a truck in the horizontal direction within restricted angles. The truck is also movable on rails.

The invention will appear more clear from the following detailed description when taken in conjunction with the accompanying drawings, showing by way of example only preferred embodiments of the inventive idea.

In the drawings:

FIG. 1 is a partially exposed side view of an internal grinder for a steel ingot mould;

FIG. 2 is a partially exposed plan view of the same;

FIG. 3 is a plan view of the same, showing the state to grind the half-right of the inside of the mould;

FIG. 4 is a plan view of the same, showing the state to grind the half-left of the inside of the mould;

FIG. 5 is a partially sectioned side view taken along the lengthwise direction of a cotter;

FIG. 6 is a plan view of main parts of a carriage and a truck, wherein a work head is removed for clarification; and

FIG. 7 is a partially sectioned view of a device for adjusting the angle of elevation of an arm and depth of cut of grinding.

A grinding wheel 1 is turnably mounted about a wheel spindle 2 provided at the tip of an elongated hollow arm 4 which is elliptic in cross section. The grinding wheel 1 is connected with an output shaft of a motor 7, fixed to a motor base 6 near the rear end of the elongated arm 4, through a known V-belt device 3 passing through the inner space of the arm 4. The arm 4 is rotatably supported by a cylindrical bearing 5, the lower portion of the bearing being rotatably pivoted to a work head 11.

A spur gear 10 is fixed to the arm 4 and is engaged with a spur gear 10a. A shaft to which the spur gear is fixed has a worm wheel 9a meshed with a worm 9 of a shaft 25 secured by the work head, so that the arm 4, as well as the grinding wheel 1, is rotated and directed to both directions, as shown in FIGS. 3 and 4, by rotating a handle 8 at one end of the shaft 25 of the worm 9 to the right and left directions. FIG. 5 shows this mechanism in detail.

The work head 11 has front and rear wheels 12 and 12a which guide it along rails above a carriage 21. The mounting of the wheels and their axles to the work head permits vertical movement of the work head relative to the wheels and rails. A shaft of the rear wheels is operatively connected to an output shaft of a speed change motor 18,-fixed to the work head 11 and having a magnetic brake 19, by means of a roller chain 20. Due to a limit switch 39, provided in the work head 11 for switching over electric sources, the work head 11 is automatically reciprocated along a predetermined length when the limit switch cooperates with dogs 40 and 400, the dogs switching by means of the limit switch.

At the fore lower portion of the bearing, there is provided means for determining the angle of elevation of the arm. A worm 14 is provided on a shaft of a handle 13 positioned at one side of the foreportion of the bearing 5 above the work head 11 as shown in FIGS. 1 and 7. An upper cap member 16 screwed with a vertical uphold screw 15, which is the shaft of a worm wheel 14a meshing with the worm 14, receives the lower portion of the bearing 5. The lower end of the uphold screw 15 is provided with a lower cap member 17 having a roller 17a which is in contact with the upper surface of a copying surface plate 27. Rotation of worm 14 moves the upper cap member 16 toward, or away from, the lower cap member, depending upon its direction of rotation. Thus, the angle of elevation of the elongated arm 4 is adjustable about a pivot connecting the bearing 5 with the work head 11 by means of rotation of the handle 13, which may be rotated in both directions.

As shown in FIG. 6, the fore end portion of the copying surface plate 27 is pivoted to the carriage 21 by a horizontal pin 28, while the rear end portion thereof is received by a wedgeshaped cotter 31 (cam) shown in FIG. 5. The cotter 31 is connected to a spindle 30 by screw threads thereof. The spindle 30 is mounted to the carriage 21, so that, by rotating a handle 29 provided at one end of the spindle, the cotter is moved to right and left along the transverse direction of the carriage. Thus, the angle of the copying surface plate 27 about the horizontal pin 28 is adjustable. With the result that the angle of elevation of the arm 4 running above the copying surface plate 27 is also adjusted by determining the inclination or shape of the copying surface plate. V

The carriage 21 is pivoted to a truck 32 at substantially the center portion thereof by means of a vertical pin 22 as shown in FIG. 6. A spindle 45 having a screw thread is pivoted to the carriage 21 at one end thereof by a pin 26 and is also fixed to the truck 32 at the other end portion thereof. The screw thread of the spindle 45 meshes with a bevel gear 24a which in turn meshes with another bevel gear 24. A handle 23 is provided to one end of a shaft of the bevel gear 24, so that, by rotating the handle 23 in either direction, the carriage 21 is moved about the vertical pin 22 in either direction within the predetermined horizontal angles, as shown in FIG. 3 and FIG. 4. The carriage has the rails on which the wheels of the work head are moved.

The truck 32 has four wheels 33 and 33a moved along two rails 38. A spur gear 37a fixed to one of the wheel axles meshes with another spur gear 37 which is rotatable by a handle 35. The truck is therefore moved right and left along the rails 38.

The grinding operation performed by using the present apparatus shall be described hereinafter in detail. A steel ingot mould 41, whose interior is to be ground, is placed upon a sup port provided in front of the present apparatus. Generally, the mould 41 is greatly deformed at the lower inside thereof, while the upper inside is not so deformed. In order to grind the inside of the mould, in accordance with its degree of deformation, the angle of elevation of the copying surface plate 27 as well as the devices thereon are adjusted by rotation of the handle 29. When the right side of the mould is to be ground for the first time, the handle 8 is rotated to direct the grinding wheel to the right side, as shown in FIG. 3, and then the handle 23 is rotated to rotate the carriage 21 as well as the devices thereon about the pin 22 along the horizontal plane so that the grinding wheel 1 may be parallel to the inner right wall of the mould. The length along which the grinding wheel 1 is moved back and forth is determined by the length of the mould, and the position of the dogs 40 and 40a is determined by that length.

The motors 7 and 18 are driven to rotate the grinding wheel 1 and to move it back and forth, respectively. While the motors 7 and 18 are in motion, the handle 13 and, if desired, the handle 29, are rotated to adjust the depth of cut of the grinding wheel 1 and the degree of parallelness between the grinding wheel and the inner wall of the mould in accordance with the degree of deformation of the mould. The grinding wheel 1 is moved from the right side to the left side by rotating the handle 35. By way of an example of the preferred condition for grinding, the forward and rearward speed of the grinding wheel is more than 15 m./min. and the lateral movement of the grinding wheel is from to 30 mm. for each reciprocal movement of the grinding wheel. When the inner right half of the mould is finished being ground, if desired, the rotation of the grinding wheel and the back and forth movement thereof are stopped and then the grinding wheel 1 is directed to the left as shown in FIG. 4, by rotating the handle 8. The inner left side of the mould is ground in the same way as the grinding of the inner right side.

When a special mould, for example, a mould having a curvature of radius R at the corner thereof, is to be ground, the upper surface of the copying surface plate is replaced with a plate having the same shape as the mould. The movement of the grinding wheel, therefore, corresponds to the inner shape of the mould.

The internal grinder for ingot mould is so constructed that many advantages will be effected, as follows:

The adjustment to adapt the grinding wheel correctly to the inclination of the right and left inner sides of the mould and to determine the depth of cut of the mould is performed while the grinding is in operation. This type of adjustment is possible because the grinding wheel is turnably mounted on one side of the tip of the elongated arm, which is received upon the work head, so as to be rotated about the axis thereof together with the drive means for the grinding wheel and to be elevated along a vertical plane including the axis of the arm. As the work head includes means to reciprocate the work head automatically along the lengthwise direction of the carriage for a predetermined length, the straight reciprocal motion of the grinding wheel is automatically performed inside of the mould along the lengthwise direction thereof, eliminating any lateral injury to the mould. The products produced by pouring melted iron into the mould and then processed through rolling mills are much improved in quantity.

As the copying surface plate is pivoted to the carriage to move within the restricted angles of elevation and receives the lower end of the adjusting means for angle of elevation of the arm, the arm as well as the grinding wheel is guided and reciprocated along the inclination of the copying surface plate. Therefore, when a large mould, for example, a mould weighing 30 tons, is to be ground, the mould is stationary placed upon a support and then the angle of elevation of the copying surface plate is determined, for example, to correspond to the inclination of the inner wall of the mould so that the arm as well as the grinding wheel may be reciprocated along the inclination of the inner wall of the mould, thereby providing a positive and automatic grinding and alignment operation for moulds of different shapes and internal dimensions. Further, even if the internal shape of the mould is a square-shaped or a round-shaped, or even if a mould to be ground is large or small, the grinding operation is performed at a high efficiency. As the angle of elevation of the arm is adjusted, firstly by the angle of the copying surface plate and secondly by rotation of the handle 13, the desirable and delicate adjustment of grinding is performed.

Although the invention has been described with reference to a particular embodiment thereof, it can be modified in various ways.

What is claimed is:

1. An internal grinder for steel ingot moulds comprising a grinding wheel device turnably mounted at the tip of an elongated arm, drive means for said grinding wheel device, a work head rotatably supporting said arm, means to rotate said arm about an axis of the arm, means provided below said arm to adjust the angle of elevation of the arm, a copying surface plate receiving an end of said adjusting means to adjust an angle of elevation of the arm, a carriage, said plate being pivoted at one end thereof to said carriage so as to be elevated within restricted angles, said carriage receiving the work head, means to reciprocate said work head in the lengthwise direction of said arm, and a movable truck with said carriage mounted thereon so as to rotate said carriage within restricted hon'zontal angles.

2. An internal grinder for steel ingot moulds as claimed in claim 1 and also comprising means provided in said work head for reciprocating said work head automatically above the carriage along a predetermined length and means for moving said truck in the transverse direction of the truck.

3. An internal grinder for steel ingot moulds as claimed in claim 1, wherein said copying surface plate has a shape corresponding to the inner shape of the ingot mould and is replaceable with other plates so as to correspond with other shapes of the mould.

4. An internal grinder for steel ingot moulds as claimed in claim 1, wherein said carriage comprises rails on both sides thereof and said work head is reciprocated thereon by wheels.

5. An internal grinder for steel ingot moulds as claimed in claim 1, wherein said means to adjust an angle of elevation of the arm comprises a wheel to run along the shape and inclination of the copying surface plate. 

1. An internal grinder for steel ingot moulds comprising a grinding wheel device turnably mounted at the tip of an elongated arm, drive means for said grinding wheel device, a work head rotatably supporting said arm, means to rotate said arm about an axis of the arm, means provided below said arm to adjust the angle of elevation of the arm, a copying surface plate receiving an end of said adjusting means to adjust an angle of elevation of the arm, a carriage, said plate being pivoted at one end thereof to said carriage so as to be elevated within restricted angles, said carriage receiving the work head, means to reciprocate said work head in the lengthwise direction of said arm, and a movable truck with said carriage mounted thereon so as to rotate said carriage within restricted horizontal angles.
 2. An internal grinder for steel ingot moulds as claimed in claim 1 and also comprising means provided in said work head for reciprocating said work head automatically above the carriage along a predetermined length and means for moving said truck in the transverse direction of the truck.
 3. An internal grinder for steel ingOt moulds as claimed in claim 1, wherein said copying surface plate has a shape corresponding to the inner shape of the ingot mould and is replaceable with other plates so as to correspond with other shapes of the mould.
 4. An internal grinder for steel ingot moulds as claimed in claim 1, wherein said carriage comprises rails on both sides thereof and said work head is reciprocated thereon by wheels.
 5. An internal grinder for steel ingot moulds as claimed in claim 1, wherein said means to adjust an angle of elevation of the arm comprises a wheel to run along the shape and inclination of the copying surface plate. 